A recording device comprises a first transmission unit, a switching and control unit, a sound quality sampling and encoding-decoding unit, a second transmission unit, a data access unit, a data writing unit, and a memory unit. A first digital audio source signal of an electronic device is transmitted from the first transmission unit to the switching and control unit. The sound quality sampling and encoding-decoding unit is electrically connected to the switching and control unit, receives and converts the aforementioned signal into a first digital audio signal and a first analog audio source signal. A second analog audio source signal of an audio receiving and transmitting device is converted into a second digital audio signal by the sound quality sampling and encoding-decoding unit. The data writing unit receives the first and second digital audio signals and writes the first and second digital audio signals into the memory unit.